Hematological disorders related cerebral infarctions are mostly multifocal

Leukemia and risk of stroke: a Mendelian randomization analysis

BACKGROUND

Observational studies suggest an association between leukemia and stroke, but causality remains unclear. Certain leukemia types may increase stroke risk, but variations exist in stroke and mortality rates across leukemia subtypes. This study employed Mendelian randomization (MR) to investigate links between leukemia subtypes and stroke.

METHODS

We conducted a two-sample Mendelian randomization (TSMR) study utilizing genetic variants linked to various subtypes of leukemia as instruments to investigate their causal effects on stroke, specifically ischemic stroke (IS) and intracerebral hemorrhage (ICH). The leukemia dataset comprised 456,276 subjects from the UK Biobank, while the stroke dataset was sourced from the FINNGEN consortium, encompassing 212,774 participants.

RESULTS

In the present study, there was suggestive evidence that genetically predicted chronic lymphocytic leukemia (CLL) is associated with ischemic stroke (odds ratio, 1.02; 95% confidence intervals, 1.01-1.05; P = 0.024), but no significant association was observed with intracerebral hemorrhage (ICH) (0.74; 0.99-1.03; P = 0.237). Additionally, chronic myeloid leukemia (CML), acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML) was no significant associations between with stroke according to genetical prediction even if heterogeneity test and pleiotropic test was performed.

CONCLUSIONS

Our Mendelian randomization analysis revealed that chronic lymphocytic leukemia (CLL) was associated with an increased risk of ischemic stroke (IS) but not intracerebral hemorrhage (ICH). Conversely, there was no evidence supporting causal associations of chronic myeloid leukemia (CML), acute lymphoblastic leukemia (ALL), or acute myeloid leukemia (AML) with either type of stroke. These findings enhance our comprehension of the intricate interplay between various leukemia subtypes and the risk of stroke. Further research is essential to delve into the underlying mechanisms and potential clinical implications of these observed associations.

Characteristics of Multiple Acute Concomitant Cerebral Infarcts Involving Different Arterial Territories

(1) Background: Multiple acute concomitant cerebral infarcts (MACCI) are relatively uncommon. Data regarding the characteristics and outcomes of patients with MACCI are lacking. We, therefore, aimed to characterize the clinical features of MACCI. (2) Methods: Patients with MACCI were identified from a prospective registry of stroke patients admitted to a tertiary teaching center. Patients with an acute single embolic stroke (ASES) involving only one vascular bed served as controls. (3) Results: MACCI was diagnosed in 103 patients who were compared to 150 patients with ASES. MACCI patients were significantly older (p = 0.010), more often had a history of diabetes (p = 0.011) and had lower rates of ischemic heart disease (p = 0.022). On admission, MACCI patients had significantly higher rates of focal signs (p < 0.001), an altered mental state (p < 0.001) and seizures (p = 0.036). The favorable functional outcome was significantly less common in patients with MACCI (p = 0.006). In the multivariable analysis, MACCI was associated with lower chances of achieving favorable outcomes (odds ratio: 0.190, 95% CI: 0.070-0.502). (4) Conclusions: There are important differences in clinical presentation, comorbidities and outcomes between MACCI and ASES. MACCI is less often associated with favorable outcomes and could represent a more severe form of a stroke compared with a single embolic stroke.

Molecular Genetics of Thrombotic Myeloproliferative Neoplasms: Implications in Precision Oncology

Classical BCR-ABL-negative myeloproliferative neoplasms (MPN) include polycythaemia vera, essential thrombocythaemia, and primary myelofibrosis. Unlike monogenic disorders, a more complicated series of genetic mutations are believed to be responsible for MPN with various degrees of thromboembolic and bleeding complications. Thrombosis is one of the early manifestations in patients with MPN. To date, the driver genes responsible for MPN include JAK2, CALR, MPL, TET2, ASXL1, and MTHFR. Affords have been done to elucidate these mutations and the incidence of thromboembolic events. Several lines of evidence indicate that mutations in JAK2, MPL, TET2 and ASXL1 gene and polymorphisms in several clotting factors (GPIa, GPIIa, and GPIIIa) are associated with the occurrence and prevalence of thrombosis in MPN patients. Some polymorphisms within XRCC1, FBG, F2, F5, F7, F12, MMP9, HPA5, MTHFR, SDF-1, FAS, FASL, TERT, ACE, and TLR4 genes may also play a role in MPN manifestation. This review aims to provide an insightful overview on the genetic perspective of thrombotic complications in patients with MPN.

Risk Factors of Ischemic and Hemorrhagic Strokes During Venovenous Extracorporeal Membrane Oxygenation: Analysis of Data From the Extracorporeal Life Support Organization Registry

OBJECTIVES

Stroke is commonly reported in patients receiving venovenous extracorporeal membrane oxygenation, but risk factors are not well described. We sought to determine preextracorporeal membrane oxygenation and on-extracorporeal membrane oxygenation risk factors for both ischemic and hemorrhagic strokes in patients with venovenous extracorporeal membrane oxygenation support.

DESIGN

Retrospective analysis.

SETTING

Data reported to the Extracorporeal Life Support Organization by 366 extracorporeal membrane oxygenation centers from 2013 to 2019.

PATIENTS

Patients older than 18 years supported with a single run of venovenous extracorporeal membrane oxygenation.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 15,872 venovenous extracorporeal membrane oxygenation patients, 812 (5.1%) had at least one type of acute brain injury, defined as ischemic stroke, hemorrhagic stroke, or brain death. Overall, 215 (1.4%) experienced ischemic stroke and 484 (3.1%) experienced hemorrhagic stroke. Overall inhospital mortality was 36%, but rates were higher in those with ischemic or hemorrhagic stroke (68% and 73%, respectively). In multivariable analysis, preextracorporeal membrane oxygenation pH (adjusted odds ratio = 0.10; 95% CI, 0.03-0.35; p < 0.001), hemolysis (adjusted odds ratio = 2.27; 95% CI, 1.22-4.24; p = 0.010), gastrointestinal hemorrhage (adjusted odds ratio = 2.01; 95% CI 1.12-3.59; p = 0.019), and disseminated intravascular coagulation (adjusted odds ratio = 3.61; 95% CI, 1.51-8.66; p = 0.004) were independently associated with ischemic stroke. Pre-extracorporeal membrane oxygenation pH (adjusted odds ratio = 0.28; 95% CI, 0.12-0.65; p = 0.003), preextracorporeal membrane oxygenation Po2 (adjusted odds ratio = 0.96; 95% CI, 0.93-0.99; p = 0.021), gastrointestinal hemorrhage (adjusted odds ratio = 1.70; 95% CI, 1.15-2.51; p = 0.008), and renal replacement therapy (adjusted odds ratio=1.57; 95% CI, 1.22-2.02; p < 0.001) were independently associated with hemorrhagic stroke.

CONCLUSIONS

Among venovenous extracorporeal membrane oxygenation patients in the Extracorporeal Life Support Organization registry, approximately 5% had acute brain injury. Mortality rates increased two-fold when ischemic or hemorrhagic strokes occurred. Risk factors such as lower pH and hypoxemia during the pericannulation period and markers of coagulation disturbances were associated with acute brain injury. Further research on understanding preextracorporeal membrane oxygenation and on-extracorporeal membrane oxygenation risk factors and the timing of acute brain injury is necessary to develop appropriate prevention and management strategies.

Recurrent ischaemic cerebrovascular events as presenting manifestations of myeloproliferative neoplasms

BACKGROUND AND PURPOSE

Myeloproliferative neoplasms (MPNs) - polycythemia vera, essential thrombocythemia and primary myelofibrosis - are associated with increased risk for ischaemic cerebrovascular events (ICVEs). Due to their low prevalence, MPNs often remain undiagnosed as the cause of ICVEs.

METHODS

Case records at the University of Tübingen between 2014 and 2017 were screened to identify patients with MPN-related ICVEs. Clinical features, brain imaging, laboratory findings, applied treatments and neurological outcomes were assessed.

RESULTS

In all, 3318 patients with ICVEs were identified, and amongst them 17 patients with MPN-related ICVEs were included in a retrospective study. In 58% of these patients, ICVEs were the first manifestation of the underlying MPN; 24% presented with transient ischaemic attack and 76% with ischaemic stroke. Potentially concurrent ICVE etiologies were noted in 70% of the patients. The majority (94%) of patients were positive for the JAK2 V617F mutation, whilst in 29% recurrent ICVEs (range two to three) were noted prior to MPN diagnosis. Early MPN diagnosis and management was the only significant prognostic factor for ICVE recurrence (P < 0.001).

DISCUSSION

Evidence is provided that, although rare, MPNs represent an underdiagnosed cause of recurrent ICVEs. High clinical awareness is warranted to identify an underlying MPN in patients presenting with sustained, abnormal blood count findings. Clinical algorithms for prompt MPN diagnosis and initiation of MPN treatment (e.g. cytoreductive therapy, phlebotomy) are required. As MPN management comprises a significant protective factor against ICVE recurrence, induction of MPN treatment should be regarded as an integral component of secondary stroke prevention in MPN-associated ICVEs.

Vertebrobasilar Artery Stroke as the Heralding Sign of Systemic Lupus Erythematosus

Cerebral ischemia because of vertebrobasilar insufficiency (VBI) rarely presents as an initial sign within the systemic lupus erythematosus (SLE) population, and there are very few case reports supporting this manifestation. This report details 3 different patients with SLE who experienced VBI as an initial manifestation. Patient 1 was a 24-year-old female who developed a bilateral pontine lesion as a consequence of basilar artery stenosis. Patient 2 was a 34-year-old male with an acute ischemic lesion on the right side of his cerebellum and pons because of significant stenosis in the distal segment of the right vertebral artery. Patient 3 was a 37-year-old female, previously diagnosed with multiple sclerosis, with multiple lesions in her cerebellum and pons bilaterally. Further investigations within this case revealed severe stenosis of the left vertebral artery. The diagnosis of SLE was based on clinical presentations such as myalgia, skin rashes, ulcers, and fatigue along with relevant laboratory findings including positive anti ds-DNA antibody and depressed levels of complement C3 and C4 proteins. In young patients with multifocal ischemic lesions or infarcts in the posterior cerebral circulation system, physicians should investigate for less common etiologies such as SLE.

Significance of Multiple Acute Ischemic Lesions on Initial Diffusion-weighted Imaging in Stroke Patients and Relation of Toast Classification

Background

It is important to know whether or not the stroke risk factors and etiologies of patients with multiple acute infarcts are different to those of patients with a single acute infarct.

Aim

The frequency of multiple acute infarct was investigated in ischemic stroke patients and a comparison was made of the characteristics of stroke patients with and without multiple acute infarct.

Patients and Methods

We reviewed the clinical records of 988 ischemic stroke patients who were admitted within 1 week of the onset of stroke and diffusion-weighted imaging (DWI) was performed on first presentation. The clinical characteristics, laboratory, and imaging results were noted from the patient records. According to the DWI findings, the patients were separated into three groups as those with a single acute infarct in a single vascular territory (SI group), those with multiple acute infarcts in a single vascular territory (SMI group) and those with multiple acute infarcts in multiple vascular (MMI group) territories. The frequency of multiple acute infarcts was investigated, and a comparison was made of the characteristics of stroke patients with and without multiple acute infarcts.

Results

The SMI group included 119 (12%) patients and the MMI group 126 (12.8%). The most common mechanisms of multiple acute infarcts are large artery atherosclerosis and cardiac origin emboli. Moreover, the risk factors most determined were hypertension, diabetes mellitus, and hyperlipidemia in the MMI group.

Conclusion

No difference was determined between the groups in respect of stroke etiology and risk factors.

Preservation of neuronal functions by exosomes derived from different human neural cell types under ischemic conditions

Stem cell-based therapies have been reported in protecting cerebral infarction-induced neuronal dysfunction and death. However, most studies used rat/mouse neuron as model cell when treated with stem cell or exosomes. Whether these findings can be translated from rodent to humans has been in doubt. Here, we used human embryonic stem cell-derived neurons to detect the protective potential of exosomes against ischemia. Neurons were treated with in vitro oxygen-glucose deprivation (OGD) for 1 h. For treatment group, different exosomes were derived from neuron, embryonic stem cell, neural progenitor cell and astrocyte differentiated from H9 human embryonic stem cell and added to culture medium 30 min after OGD (100 μg/mL). Western blotting was performed 12 h after OGD, while cell counting and electrophysiological recording were performed 48 h after OGD. We found that these exosomes attenuated OGD-induced neuronal death, Mammalian target of rapamycin (mTOR), pro-inflammatory and apoptotic signaling pathway changes, as well as basal spontaneous synaptic transmission inhibition in varying degrees. The results implicate the protective effect of exosomes on OGD-induced neuronal death and dysfunction in human embryonic stem cell-derived neurons, potentially through their modulation on mTOR, pro-inflammatory and apoptotic signaling pathways.